When an alternation contains multiple alternatives that consist of a single character, it can be rewritten as a character class. This should be
preferred because it is more efficient and can even help prevent stack overflows when used inside a repetition (see rule S5998).
Noncompliant code example
Pattern.compile("a|b|c"); // Noncompliant
Compliant solution
Pattern.compile("[abc]");
// or
Pattern.compile("[a-c]");
